1. Field of the Invention
The present invention generally relates to semiconductor devices, and more particularly, to interface method of semiconductor devices.
2. Description of the Related Art
It is necessary, in some cases, to transfer data between semiconductor devices. The following case of transferring two sets of 16 bit width data, D1 and D2, sequentially from a semiconductor device A to another semiconductor device B, will be considered as an example.
D1: 1100110011001100
D2: 1100110011001101
In this case, only the last bit is different from each other, and the other bits are the same. Generally, in case of sequential data of moving pictures for example, data is almost the same as the next data, and only a part of data is different. Thus, uncompressed data is redundant and transferring uncompressed data is not efficient. Data is usually compressed, then transferred or stored into recording medium.
In some situations, however, it is necessary to transfer uncompressed data between semiconductor devices. When image data is processed, for example, uncompressed data or decompressed data may be transferred between semiconductor devices.
When raw data is transferred without data compression, however, data contains much unnecessary information, and unnecessary electric power is consumed.